An Efficient Lagrangean Relaxation-based Object Tracking Algorithm in Wireless Sensor Networks

In this paper we propose an energy-efficient object tracking algorithm in wireless sensor networks (WSNs). Such sensor networks have to be designed to achieve energy-efficient object tracking for any given arbitrary topology. We consider in particular the bi-directional moving objects with given frequencies for each pair of sensor nodes and link transmission cost. This problem is formulated as a 0/1 integer-programming problem. A Lagrangean relaxation-based (LR-based) heuristic algorithm is proposed for solving the optimization problem. Experimental results showed that the proposed algorithm achieves near optimization in energy-efficient object tracking. Furthermore, the algorithm is very efficient and scalable in terms of the solution time

Mobile Wireless Sensor Networks: An Overview

Mobile wireless sensor networks (MWSNs) have emerged and shifted the focus from the typical static wireless sensor networks to networks with mobile sensor nodes that are capable to sense the various types of events. Also, they can change their position frequently in a specific sensing area. The applications of the MWSNs can be widely divided into time-driven, event-driven, on-demand and tracking based applications. Mobile sensor node architecture, residual energy utilization, mobility, topology, scalability, localization, data collection routing, Quality of Service (QoS), etc., are the key factors to design an energy efficient MWSNs for some specific purpose. This chapter deals with an overview of the MWSNs and a few significant phenomena to design an energy efficient MWSNs to the large-scale environment

Adaptive multi-target tracking in heterogeneous wireless sensor networks

Energy efficient multiple-target tracking is an important application of Wireless Sensor Networks (WSNs). Most prior studies consider tracking multiple tar- gets as an extension of executing a single target tracking algorithm multiple times, and use a single parameter for energy efficiency. We consider various factors such as mul- tiple targets tracked by the sensor, remaining energy of the sensor and relative location of the sensor with respect to a target's motion, in order to decide the tracking state of a sensor in a distributed environment. Further, we explore and identify the effective combination of these parameters to optimize energy usage, depending on specific network conditions. We then propose the Adaptive Multi-Target Tracking (AMTT) algorithm that can recognize the network condition based on local information without centralized coordination, and uses effective parameters to achieve en- ergy efficiency

QoS Provision for Wireless Sensor Networks

Wireless sensor network is a fast growing area of research, receiving attention not only within the computer science and electrical engineering communities, but also in relation to network optimization, scheduling, risk and reliability analysis within industrial and system engineering. The availability of micro-sensors and low-power wireless communications will enable the deployment of densely distributed sensor/actuator networks. And an integration of such system plays critical roles in many facets of human life ranging from intelligent assistants in hospitals to manufacturing process, to rescue agents in large scale disaster response, to sensor networks tracking environment phenomena, and others. The sensor nodes will perform significant signal processing, computation, and network self-configuration to achieve scalable, secure, robust and long-lived networks. More specifically, sensor nodes will do local processing to reduce energy costs, and key exchanges to ensure robust communications. These requirements pose interesting challenges for networking research. The most important technical challenge arises from the development of an integrated system which is 1)energy efficient because the system must be long-lived and operate without manual intervention, 2)reliable for data communication and robust to attackers because information security and system robustness are important in sensitive applications, such as military. Based on the above challenges, this dissertation provides Quality of Service (QoS) implementation and evaluation for the wireless sensor networks. It includes the following 3 modules, 1) energy-efficient routing, 2) energy-efficient coverage, 3). communication security. Energy-efficient routing combines the features of minimum energy consumption routing protocols with minimum computational cost routing protocols. Energy-efficient coverage provides on-demand sensing and measurement. Information security needs a security key exchange scheme to ensure reliable and robust communication links. QoS evaluation metrics and results are presented based on the above requirements

Variable Power Energy Efficient Clustering for Wireless Sensor Networks 1

Abstract : Wireless sensor networks (WSN) are inheriting many application areas like environment observation, target tracking, border monitoring and battle field surveillance. To alleviate the problem of energy utilization and extending the lifetime of wireless sensor nodes, one approach is employing an effective clustering mechanism. In this paper variable power energy efficient clustering (VEEC) mechanism for wireless sensor networks has been proposed. It is a well distributed, energy efficient clustering algorithm which employs relay nodes, variable transmission power and single message transmission per node for setting up the cluster. The proposed scheme is compared with two existing distributed clustering algorithms LEACH and HEED. Simulation results clearly show an excellent improvement in average communication energy and the total energy of the wireless sensor system. Simulation study also shows the reduction in node death rate and prolongation in network lifetime compared to the two existing algorithms

Passive source localization using power spectral analysis and decision fusion in wireless distributed sensor networks

Source localization is a challenging issue for multisensor multitarget detection, tracking and estimation problems in wireless distributed sensor networks. In this paper, a novel source localization method, called passive source localization using power spectral analysis and decision fusion in wireless distributed sensor networks is presented. This includes an energy decay model for acoustic signals. The new method is computationally efficient and requires less bandwidth compared with current methods by making localization decisions at individual nodes and performing decision fusion at the manager node. This eliminates the requirement of sophisticated synchronization. A simulation of the proposed method is performed using different numbers of sources and sensor nodes. Simulation results confirmed the improved performance of this method under ideal and noisy conditions

Multi-channel wireless sensor networks : protocols, design and evaluation

Pervasive systems, which are described as networked embedded systems integrated with everyday environments, are considered to have the potential to change our daily lives by creating smart surroundings and by their ubiquity, just as the Internet. In the last decade, “Wireless Sensor Networks” have appeared as one of the real-world examples of pervasive systems by combining automated sensing, embedded computing and wireless networking into tiny embedded devices.\ud A wireless sensor network typically comprises a large number of spatially distributed, tiny, battery-operated, embedded sensor devices that are networked to cooperatively collect, process, and deliver data about a phenomenon that is of interest to the users. Traditionally, wireless sensor networks have been used for monitoring applications based on low-rate data collection with low periods of operation. Current wireless sensor networks are considered to support more complex operations ranging from target tracking to health care which require efficient and timely collection of large amounts of data. Considering the low-bandwidth, low-power operation of the radios on the sensor devices, interference and contention over the wireless medium and the energy-efficiency requirements due to the battery-operated devices, fulfilling the mentioned data-collection requirements in complex applications becomes a challenging task. This thesis focuses on the efficient delivery of large amounts of data in bandwidth-limited wireless sensor networks by making use of the multi-channel capability of the sensor radios and by using optimal routing topologies. We start with experimenting the operation of the sensor radios to characterize the behavior of multi-channel communication. We propose a set of algorithms to increase the throughput and timely delivery of the data and analyze the bounds on the data collection capacity of the wireless sensor networks

Simulation study of routing protocols in wireless sensor networks

Wireless sensor networks, a distributed network of sensor nodes perform critical tasks in many application areas such as target tracking in military applications, detection of catastrophic events, environment monitoring, health applications etc. The routing protocols developed for these distributed sensor networks need to be energy efficient and scalable. To create a better understanding of the performance of various routing protocols proposed it is very important to perform a detailed analysis of them. Network simulators enable us to study the performance and behavior of these protocols on various network topologies. Many Sensor Network frameworks were developed to explore both the networking issues and the distributed computing aspects of wireless sensor networks. The current work of simulation study of routing protocols is done on SensorSimulator, a discrete event simulation framework developed at Sensor Networks Research Laboratory, LSU and on a popular event driven network simulator ns2 developed at UC Berkeley. SensorSimulator is a discrete event simulation framework for sensor networks built over OMNeT++ (Objective Modular Network Test-bed in C++). This framework allows the user to debug and test software for distributed sensor networks. SensorSimulator allows developers and researchers in the area of Sensor Networks to investigate topological, phenomenological, networking, robustness and scaling issues, to explore arbitrary algorithms for distributed sensors, and to defeat those algorithms through simulated failure. The framework has modules for all the layers of a Sensor Network Protocol stack. This thesis is focused on the simulation and performance evaluation of various routing protocols on SensorSimulator and ns2. The performance of the simulator is validated with a comparative study of Directed Diffusion Routing Protocol on both ns2 and SensorSimulator. Then the simulations are done to evaluate the performance of Optimized Broadcast Protocols for Sensor Networks, Efficient Coordination Protocol for Wireless Sensor Networks on SensorSimulator. Also a performance study of Random Asynchronous Wakeup protocol for Sensor Networks is done on ns2